Electronics Forum | Wed Feb 05 10:31:38 EST 2003 | bpan
Hello Everyone, Is anyone out there building smt boards that have plated through vias directly located through the pads. We are seeing some of these designs and the soldering is very poor because the solder is flowing through the via. We think that w
Electronics Forum | Wed Feb 12 16:23:30 EST 2003 | russ
I agree with DDave, You have something else wrong! .100 dips with .05" lead protrusion should not bridge (in fact I would think that it would be almost impossible). Tell us about your machine, (laminar flow, A-wave, etc.., size of nozzle, wave heig
Electronics Forum | Wed Feb 19 19:46:29 EST 2003 | adlsmt
I estimate the costs about the same but we build in batches so the wave only runs a few hours a day. We do complex boards so I think its worth it plus you have to keep the machine awhile to recoup the investment in the new nozzles. If the market gets
Electronics Forum | Mon Feb 24 12:14:07 EST 2003 | gilligan
We use an EKRA E4 printer, but the concept sounds the same as far as the fiducial alignment goes. I have found that SOT-23 components work the best for fiducials - and I always make it a point to use them on our older PCB's (where the screens do not
Electronics Forum | Mon Feb 24 15:14:21 EST 2003 | blnorman
Having worked with adhesives for years, the first thing to look at if there is a failure of this type is surface contamination. The subject has been discussed here also. A structural adhesive will increase in strength with a "hotter" cure. We also
Electronics Forum | Tue Mar 11 11:56:20 EST 2003 | Mark
Please inspect the pcb were the components were "lost" Check if the glue dots were lef on the PCB.If so you have a component which has been contaminated.If the dots dont appear on the PCB,which is the more common of the 2,there is an adhesion problem
Electronics Forum | Wed Mar 26 22:17:09 EST 2003 | dlkearns1
I Like your analysis here. I dunno the whole story, but I've tracked parts popping/falling off to the metalazation of the parts, from various suppliers, as most suppliers have some type of pre-tinned coating on the leads.(not that this means anything
Electronics Forum | Fri Feb 21 20:24:09 EST 2003 | MA/NY DDave
Hi I don't have some of the names in front of me yet check out on the web anyone related to the EMPF center formerly out of Indianapolis, IN. Most these guys did not move East. Chicago has a couple of shows like SMTA and another that several of the
Electronics Forum | Fri Feb 21 19:49:36 EST 2003 | MA/NY DDave
Hi Good Luck Neil, When I first saw this process described, what you are experiencing was my first visual thoughts. Partial filling as well as huge solder voids inside of the joints. I figured for low reliability product or short life maybe this t
Electronics Forum | Fri Feb 28 01:10:32 EST 2003 | MA/NY DDave
Hi I don't know what FR4 you are using, so check it out to make sure 125 isn't too high. I have seen this done occassionally when the PCBs have bad moisture or other problemx where baking helps prior to assembly and solder, yet I haven't seen it do